| From 568be8aaf8a535f79c4db76cabe17b035aa2584d Mon Sep 17 00:00:00 2001 |
| From: Takashi Iwai <tiwai@suse.de> |
| Date: Fri, 30 Sep 2022 12:01:29 +0200 |
| Subject: ALSA: usb-audio: Fix NULL dererence at error path |
| |
| From: Takashi Iwai <tiwai@suse.de> |
| |
| commit 568be8aaf8a535f79c4db76cabe17b035aa2584d upstream. |
| |
| At an error path to release URB buffers and contexts, the driver might |
| hit a NULL dererence for u->urb pointer, when u->buffer_size has been |
| already set but the actual URB allocation failed. |
| |
| Fix it by adding the NULL check of urb. Also, make sure that |
| buffer_size is cleared after the error path or the close. |
| |
| Cc: <stable@vger.kernel.org> |
| Reported-by: Sabri N. Ferreiro <snferreiro1@gmail.com> |
| Link: https://lore.kernel.org/r/CAKG+3NRjTey+fFfUEGwuxL-pi_=T4cUskYG9OzpzHytF+tzYng@mail.gmail.com |
| Link: https://lore.kernel.org/r/20220930100129.19445-1-tiwai@suse.de |
| Signed-off-by: Takashi Iwai <tiwai@suse.de> |
| Signed-off-by: Greg Kroah-Hartman <gregkh@linuxfoundation.org> |
| --- |
| sound/usb/endpoint.c | 3 ++- |
| 1 file changed, 2 insertions(+), 1 deletion(-) |
| |
| --- a/sound/usb/endpoint.c |
| +++ b/sound/usb/endpoint.c |
| @@ -73,12 +73,13 @@ static inline unsigned get_usb_high_spee |
| */ |
| static void release_urb_ctx(struct snd_urb_ctx *u) |
| { |
| - if (u->buffer_size) |
| + if (u->urb && u->buffer_size) |
| usb_free_coherent(u->ep->chip->dev, u->buffer_size, |
| u->urb->transfer_buffer, |
| u->urb->transfer_dma); |
| usb_free_urb(u->urb); |
| u->urb = NULL; |
| + u->buffer_size = 0; |
| } |
| |
| static const char *usb_error_string(int err) |
